Device for producing aerosols



Feb. 24, 1948.

A. w. LINDQUIST Er AL DEVICE FOR PRODUCING AEROSOLS VFiled sept. 6, 1944' ,rilllllllllllllllllllllllr Q. l ily A.w. LINDQUIST C. N HUSMAN `"LO SCHROEDER l l l n l Patented Feb. 24.1948 Y 2,436.4'78 nevica Fon PnonUcmc AEnosoLs Arthur W. Lindquist, Chester N. Husman, and Herman 0. Schroeder, Orlando, Fla., assignors `to United States of America, as represented by the Secretary oi' Agriculture f Application September (i,A 1944, Serial-No. 552,860

(Granted under the act of March 3, 1883. as amended April 30, 1928; 370 0. G. 757) 1 Claim.

This application is made under. the ac t of March 3, 1883, as amended by the act of April 30, 1928, and the invention herein described and claimed, if patented, may be manufactured 'and used by or for the Government of the United States of America for governmental purposes without the payment to us` of any royalty there- This invention relates to a device for the production of finely atomized sprays of the type known as aerosols for the control of mosquitoes, flies, gnats, and other insects.

An object of this invention is the combining of an air pump and liquid tank in a compact, convenient unit which can be carried on the person, stored easily, and packed and shipped with a, minimum of weight and space.

Another object is to'avoid leakage of liquid when the device is not in use irrespective of the position in which it might be placed.

Further objects are the provision of means to increase the discharge rate of the spray and to produce finely atomized droplets or aerosols that remain suspended in the air for considerable periods of time.

Other objects and advantages of the inven Figure 2 is a vertical section of the device.

showing parts in position when it is not in use; and

Figure 3 is a section along the line 3-3 of Fig. 1.

Referring with more particularity to the drawing in which like numerals designate like parts,

near the rear of the tank I2 is slightly elevated from the bottom of the tank I2 and extends to` a valve 2|.- The body of thevalve is disposed inside the container and the needle valve 22,

-needle control 23, and packing nut 24 are disposed outside the front end of the container. Feed tubes 25 extend from the valve 2| inside the container through the wall 26 and on the outside of the container, they are connected to capillary tubes 2'1. Eachcapillary tube extends to a point opposite one of the orifices I9. These capillary tubes should, preferably, have an orifice diameter of about 0.017 inch (inside diameter) and a wall thickness of about 0.001 at the outlet.

Struts 28 are secured inside the container II to strengthen it and thereby prevent undue expansion and retraction of the walls. Such expansion and retraction would cause ejection of liquid through the capillary tubes in a coarse stream which is not desirable.

A screw cap 29 covers the filling aperture 30 of the tank. A hood 3|, above the nozzles, is

attached to the container and a slide 32 covers the ends of the capillary tubes 21 when moved in one direction and uncovers them when moved in the opposite direction. The slide is carried on the tubes 25 which serve as guide tracks. A plate 33, which is rigidly secured to the outside of wall 26 in a substantially superimposed position over cylinder I1, and which contains a plurality of orifices in direct alignment with orifices I -9, is also provided. This plate 33 serves as a means for carrying hood 3|.

In operation, this device will discharge concentrated insecticides in an exceedingly iine mist which remains suspended, and consequently effective, in the air for prolonged periods of time.

a container II, preferably fabricated of a suitable metal with crimped edges, is divided into two compartments, one of which is of cylindrical shape and comprises the barrel of an air pumpv and the other comprises a tank I2 for holding the liquid to be dispersed. A leather piston I3 and supports I4 are mounted on a plunger rod I5, which is supported by a cap I6, all enclosed in the cylinder I1, forming an air pump. By actuating the plunger rod I5 by means of the handle I8, ejection of air through a plurality4 To put the device into operation, the ends of the capillary tubes 21 are exposed by moving the slide 32 toward the valve 2I. The valve is 'then opened and the pump actuated with the handle I8. 'I'his delivers air over the ends of the capillary tubes, thereby pulling liquid from the tank and atomizing it into a spray or mist of very fine particles. When a suiiicient amount of the mist has been dispensed, the plunger is pushed in and the handle locked in position. Also, the valve is closed and the slide moved in position to cover the ends of the capillary tubes 21. In this condition, the container may be placed in a pocket on the person or stored in any position without danger of leakage.

This device, although generally useful for the dispensing of insecticides, may be used to dispense any other liquids desired. We have found 3 that 0.5 cc. ot a liquid containing about 20 to 25% active insecticidal ingredients is eilective for a space of about 1,000 cubic ieet when dispensed by a device ot this kind.

Biological tests with nies show the great superiority of our device over other types of sprayers. For example, the 24-hour mortality of houseilies exposed to the atomized spray produced by our device at intervals of 15, 30, and 60 minutes was 62, 37, and l5 percent, respectively. Qther types of sprayers gave mortalities of only 30, 20 and 4 percent when exposed in the same manner.

Similar biological tests on mosquitoes with our device gave mortalities of '10, 30, and I percent as compared to other sprayers giving mortalities of 26, 10, and 4 percent Having thus described our invention, claim:

container for holding a liquid. an air pump in said container, said container having a plurality of apertures for the discharge of air from said pump, capillary tubes on the outside of the container, each terminating at a point in the path of airdischarged from one o! said apertures, a valve, said capillary tubes being connected to the outlet of said valve, a shield slidablymounted on said container for covering the ends of said tubes when the device is not in use and for uncovering said ends when the device is to be used,a hood secured to said container in the line of movement of said slide for engaging the end of said slide when `the slide is in a position covering said ends, a

REFERENCES CTEED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 601,616 Gurnee Mar. 29, 1898 651,938 Smith June 19, 1900 663,200 Smith Dec. 4, 1900 217,474 Tolman et al. Dec. 30, 1902 1,488,125 Kline Mar. 25, 1924 1,868,893V Gentle July 26, 1932 2,040,302 Fortier May 12, 1936 2,355,550 v Nusbaum Aug. 8, 1944 OTHER REFERENCES Soap and Sanitary Chemicals, Sept. 1943 (a periodical). Page 105. Copy in Patent Olice Library, Wash. D. C. 

